The present invention relates generally to chucks for use with drills or with electric or pneumatic power drivers. More particularly, the present invention relates to a chuck of the keyless type which may be tightened or loosened by hand or by actuation of the driver motor.
Both hand and electric or pneumatic tool drivers are well known. Although twist drills are the most common tools used with such drivers, the tools may also comprise screw drivers, nut drivers, burrs, mounted grinding stones and other cutting or abrading tools. Since the tools may have shanks of varying diameter, or the cross-section of the tool shank may be polygonal, the device is usually provided with a chuck which is adjustable over a relatively wide range. The chuck may be attached to the driver by a threaded or tapered bore.
A wide variety of chucks have been developed in the art. In one form of chuck, three jaws spaced circumferentially approximately 120 degrees apart from each other are constrained by angularly disposed passageways in a body attached onto the drive shaft. The chuck is configured so that rotation of the body in one direction relative to a constrained nut engaging the jaws forces the jaws into gripping relationship with respect to the cylindrical shank of a tool, while rotation in the opposite direction releases the gripping relationship. Such a chuck may be keyless if it is rotated by hand. One example of such a chuck is disclosed in U.S. Pat. No. 5,501,473 entitled xe2x80x9cChuck,xe2x80x9d commonly assigned to the present assignee, and the entire disclosure of which is incorporated by reference herein.
Various configurations of keyless chucks are known in the art and are desirable for a variety of applications.
The present invention recognizes and addresses the foregoing considerations, and others, of prior art constructions and methods. Accordingly, it is an object of the present invention to provide an improved chuck for use with a manual or powered driver.
This and other objects are achieved by a chuck for use with a manual or powered driver having a rotatable drive shaft. The chuck includes a generally cylindrical body having a nose section and a tail section. The tail section is adapted to rotate with the drive shaft. The nose section has an axial bore formed therein and a plurality of angularly disposed passageways formed therethrough and intersecting the axial bore. A thrust bearing ring is fixed on the body between the nose section and the tail section. A plurality of jaws are slidably positioned in the passageways. Each jaw has threads formed on one side thereof and a tool engaging surface formed on the opposite side thereof. A nut is rotatably mounted about the body and is in engagement with the jaw threads so that rotation of the nut with respect to the body moves the jaws within the passageways. The nut receives the thrust ring so that the thrust ring holds the nut against forward and rearward axial movement with respect to the body. The chuck also includes a generally cylindrical sleeve in driving engagement with the nut.